Manufacturers constantly seek to improve on prior designs. For example, in some markets manufacturers attempt to obtain electric apparatuses which are smaller than the corresponding devices of a previous generation. A small size, however, can be problematic due to the heat generated by the various internal components. When the size of the apparatus decreases, the amount of space available for various cooling solutions becomes smaller.
In a known design using forced convection, a fan is utilized to generate an airflow through a housing of an electric apparatus. The electric components to be cooled are all located in the generated airflow. Therefore, heat dissipated by the electric components during use is transferred to the airflow and further on to the surrounding environment. Suitable dimensioning of the fan and the amount of air passing through the housing of the electric apparatus makes it possible to ensure that the temperature inside the housing remains at a suitable level.
One attribute of such designs allows for dirt and dust to enter the housing of the electric apparatus with the airflow. The amount of dirt and dust entering the housing increases as the amount of air in the airflow increases. This condition can be a problem in unclean environments, as some of the electric components of the electric apparatus can malfunction when too much dirt is accumulated inside the housing. Efficient filtering is not always an option, as this can call for maintenance by service personnel and additionally space which increases the size of the electric apparatus.